Art of heating.



A, ROEHTS. ART 0F HEATING.

APPLICATIQN FILED AUG. 5,l |915.

Patented Oct. 10, 1916.

2 SHEETS-S HEET l A. ROBERTS.

` ART OF HEATING.

APPLICATION man Aucm. |915.

l .Patented 0111.111916.

2 SHEETS-SHEET 2 ZZV/7% /Z//Z//V NN@ @XW @@15. .mm QN mm .aan oFFioE.

ARTHUR ROBERTS, VANSTON, ILLINOIS.

ART or HEATING.

esoneri.

Specification of Letters Patent.`

Patented Oct. 10,- 1916.

Application filed August 5,y 1915. Serial No. 43,753.

To all whom t may concern Be it known that I, ARTHUR Ronnic'rs, acitizen of the United States, residing at Evanstoiu county o f Cook, andState of Illinois, have inventedv certain new and useful Improvements inthe Art of Heating, of`

which the following is a specification.

The present invention `has reference to certain improvements in the artof heating, and particularly the art of heating walls, such, forexample, as coke oven walls. The discoveries herein disclosed and shown,by

way of example, as being applied to a particularuse are verywell-adapted for use in the art of coke manufacture, but it will appearthat the usefulness of the invention. is in nowise limited to thisparticular art.

The features of the present invention may be used, either in connectionwith the trans-l fer of heat from the hot gases to a wall, as in thecase of a coke oven heating wall, or in connection with the transfer ofheat from the hot wall to the comparatively cool gas orair, as in thecase o-f arecuperating wall; in the first case the heat is transferredto the wall by the bombardment of the hot gas against the wall, therebyextracting the heat from the hot' gas and transferring it into the wallby impingement; in the second case,

the air is caused to absorb heat from the wall by vthebombardment oftheair against the wall, thereby extracting the heat from the hot wallby the impingeinent of the cool-air .K against the hotter wall.Furthermore, said 40 contemplate equally a converse transfer.

` manner, where I usethe term gas, it will principles are vequallyapplicable fo-r Athe transfer of heat between a wall and either `gas orair. Hence, where in this specification and the claims to'follow, I makereference to the transfer of heat from the gas or air to the wall, itwill be understood that I from the wall to the gas or air ;V and in likebe understood that I contemplate also air within the meaning of thatterm.

Where it is desired to effect transfer of heat between gas and a Wall orother structure, suoli heat transfer may be accom- "plished byradiation, convection, or conduction. Air and gas constitute relativelypoor conductors of heat, and, therefore, the transfer of heat from thoselayers of gas sepairated 'a substantial distance from theqsur- .face ofthe -wall into or from the wall itself, is greatly hindered and lessenedbyl this fact. Therefore' any means -or method which tends to preventthe formation ofseparate layers of gas or air, Which layers ordinarilytravel parallel to the wall; and which means or method serves to driveall sol portions of the gas into intimate contact `with the wall, willaccelerate and increase the heat transfer between the gas and wall. Ifthe heat is to berapidly transferred between the gas on the one hand,and the Wall or other body on-the other hand, and by the terni rapidtransfer, I mean the transfer of a comparatively large number of. heatunits per unit of area in a given time interval, then such transfer mustbe accomplished rather by convection Athan by conduction or radiation.

brought into as intimate contact as possible with the surface. By sodoing, there will be an opportunity for each portion of gas to come intothat condition or position Where the heat transferv can be most readilyI accomplished.

I have discovered the fact that if a currentor stream of gas be causedto travel along a flue or 'other relatively large passage, there willcling to the surfaces of such flue or other passagev a more or lessthick layer of gas, said layer remaining relatively stationary on thesurface of' the tlue,'and serving to very largely isolate or insulatethe `gas within'the central portion of the iue from the surface to beheated. The existence or presence of this layer of inert gas nia-y besaid to be due to skin friction of the stream of gas on the surface.viously set forth,su cli a layer of inert gas will act as a heatinsulating layer or medium, so that it will largely and seriously l Thevarious portions or masses of the body of gas must be successively Aspre- I have discoveredv the fact that, ifll the gas be 4driven withviolence 'and frequency against the surface, and if the body of the gasbe considerably sub-divided into various portions, so that eventuallypractically every portion of the body of gas be brought into intimatecontact with the surface, avery greatly improved heat transferringaction will be secured, with the result that not only willthe percentageof transferable heat be greatly increased,bnt` also it will be possibleto cause a much greater heat transfer per unit of area. This will mean,in the case of a wall which is being heated, that a much greaterpercentage of the total heat of the gas can be abstracted, and, further-`more, a much higher temperature of the `wall can be secured than wouldotherwise be possible. j

In the case, for example, of a coke oven heating wall, the gasescommence their heating action at what maybe termed the maximumtemperature, being at a point adjacent to their point of entry into theheating wall, and thereafter they become cooler as they approach thepoint of exit, at which point they may be termed 'spent7 gases. If theheat transfer per unit of area and per degree of di li'erence intemperature on the two sides of the wall, is constant in all portions ofthe wall, it will necessarily follow that thev'all lwill be most greatlyheated adjacent to the point of entry of the gases, and the amount orextent of heating will diminish toward `the point of exit of the gases.The result will be that the wall will be unevenly heated. beingmaterially hotter in some portions than inothers.

I have discovered the fact that, by regulating or adjusting or modifyingthe amount of the impingementaction of the hot gases in the differentportions of the wall, increasing the impingement per unit of area towardthe point of exit as compared to the impingement per unit of areaadjacent to the point ofentry of the gases, I can secure a practicallyuniform amount of heat transfer per unit of area at all points withinthe wall being heated, so that the resulting temperature at all pointsofthe wall will be practically the same, notwithstanding the fact that theheating gases are becoming cooler or more spent as they approach thedischarge point. To accomplish this result. I may cause the rate ofimpingement of the gases to increase in suchvratio that the rate ofpercentage of absorption of heat correspondingly increases as the gasescool, there-- by keeping or maintaining constant at all points theamount of heat absorbed into each unit of area.

Therefore, it may be stated that in broad terms my invention consists incausing thegases'to undergo an impingement action so als to prevent theformation of layers of inert gas adjacent Ato the surfaces being heated,and so as to ultimately insure the Contact with such surface ofpractically each and every portion of the gas, and so as to -drive thegas forcibly against the surface4 'therein illustrated, largely as amatter of convenience, the features of my invention as applied to theart of heating a coke oven. Furthermore, the general type of coke ovenconstruction shown in the said drawings is also shown in my ,LettersPatent of the United States, No. 1.132,685, issued to me March 23, 1915.It will he understood, however. that the invention is in nowise limitedto the heating of coke ovens, nor, for that matter, to the transfer ofheat from the gas to the wall or other surface, but that the featuresmay also be used for the heating of other structures,'or, for thatmatter, for the transfer of heat from the wall or other structure to thegas or air.

In the said figures: Figure 1 shows a cross section through a coke ovenconstruction embodving the features of the invention,

ovens adjacent to its side portions; Fig. 2

`shows a vertical section taken on the line 22 of Fig. 1, looking in thedirection of the arrows; Fig. 3 shows a fragmentary horizontal sectiontake on the line ot Fig. 1, looking in the direction of the arrows; Fig.4 shows a fragmentary horizontal section taken on the line i--4 of Fig.1, looking in the direction of the arrows; Fig. 5 shows a, fragmentaryhorizontal section taken on the line 5--5 of Fig. 1, looking in thedirection of the arrows; Fig. G shows a plan view of one form ofinuiingement block used in the construction illustrated; Fig. 7 shows avertical elevation of the block shown `in Fig. 6; Fig. 8 shows a planview of 'another type of impingement block, the same being adapted tocooperate with the block shown inFigs. G and 7; Fig. 9 shows a sideelevation of the bloclr'shown in plan in Fig. Fig. 10 shows afragmentary section through a modified construction of a'wali in whichuse is made of a zigzag flue, theimpingement in this case being securedby the forcible striking of gases against the sides of said iue.

In the arrangement illustrated, the numeral 10 designates thecarbonizing chamber of the oven to which the features of the presentLinvention have been applied. The walls 11 and 12 are the heatingwalls.Along the upper portion of each heating wall is a row of burners 13which deliver the combustion mixture into theiheating Walls. In theararngernent illustrated, each burner delivers its combustion mixtureinto a short iue or individual passageway 14 in the upper portion of theheating wall.

burningvgases trav'el down through the passage 14, heat is abstractedfromthem 1n the usual manner, which I will term skin fricand bottonisurfaces of their central portions i substantially as illustrated inFigs. 6, 7, 8, and 9. The end portions of these blocks are so formedthat they complement each other, and, therefore, may be set togetheralter- .nately in the courses, so as to build up the -wall from the twoforms of block.

The wall as thus constructed willbe provided on its interior portionwith a mesh work of communicating passages, said passages being formedby the presence of the. notches or Vrecesses inthe blocks. By staggeringthe alternate courses of blocks, so as to make them break joints, asshown in Fig. 2, the mesh of passages. will be zigzaged, asillustrated,so that gases passing down through these .passages will not be able totravel by a direct course, but will be thrown repeatedly back and forthand against the blocks. Beneath each of the heating walls, I haveillustrated a Achannel 16, wherein the spent gases are received from theentire lower edge of the heating wall. Beneaththe sole is the passage17, into which the spent gases from the passages 16 are collected bymeans of cross connections 18.

Referring again to Figs. 6, 7, 8, and 9, the block shown in Figs. 6 and7 has the recesses 19 and 20 on its side portions, and the recess 21 onits bottom portion. Its ends 22 j and 23 are beveled or taperedinwardly. The block shown in Figs. 8 and 9 is provided with'siderecesses 24 and 25, and with a bot- Vtom recess 26, and its end portions27 and 28 are beveled or tapered outwardly. The size of the. passages.or openings formed within the body of the wall by the presencev of therecesses will be determined by or be dependent upon the size of thevarious recesses. Therefore, it is only necessary to select blockshaving recesses of desired size in order to secure passages of thedesired size within the body of the wall.

`An examination of Fig. 2 will show that,

- as the gases travel from the burners toward Athe-point of exit,theyare subjected to very rapid and violent contact or impingementagainst the blocks of the wall. The velocity of the gases will'be veryhigh, so that the .impingement action will be still further increased,and the gases will be driven rapidly with great violence againsta largenumber of blocks before they are able to reach the exit. Thisarrangement is to be distin- As the.

vention also consists invarying the amount of impingement action as thegases travel from the entrance to the exit, so that, as -they becomemore Vand more spent or exhauslted, nevertheless substantially the samenumber of heat units will be taken into each unit area of the wall atevery point in the wall. This will secure ansubstantially uniformiheating or temperature of the wall at all points from .the entrance tothe exit. With such an arrangement, the wall will necessarily' beuniformly heated, and, therefore, this additional feature is of greatvalue" 1n those constructions where 1t 1s desired to secure a uniformtransfer of heat through all portions of a wall of considerable area,as,

' for example, a coke oven heating wall. This varied amount ofimpingement action may be secured in different ways, one of whichv'consists in varying the sizes or openings of the gas passages atvarious points in the wall, so that the impingement action will increaseas the gases approach the point of eX- haust. In the particularconstruction illustrated, the variation in the sizes of the passages isaccomplished by varying the sizes of the lrecesses of the blocks. Thus,examination of Fig. 2 shows very' distinctly that `the passages in theupper portion of the mesh, that is, just below the line 15, are verymuch larger in section. than those in the lower portion'of the mesh,that is, just above the channel 16. lVhile I have shown the variation ofimpingement action as being se- ,ing in zigzag manner in the samelgeneral direction. 'The bends are of such 4frequency and sharpness thatthe gases are driven repeatedly and with great violence against thewalls or sides of the fiue, so that an impingement action is securedvery similar, in many respects. to the action in the construction shown,particularly in Figs. 1l to .9. inclusive.

It will also be seen from examination ofFig.

10 that, in the arrangement herein illus-A trated, the size of the fluediminishes in the direction of gas travel so that the gases are forcedto travel with increased rapidity as they approach the exit, therebyincreasing the frequency and violence olf the in'ipingement.

As an illustraticai of one instance in 'which the features of inventionherein disclosed have been applied, l `will mention the follow'- ing: lna given installatirgm, the impinge.- ment portion of a colic ovenheating wall comprises twenty-four courses of blocks measured betweenthe course l5 and the channel 16 of l(` 2. These twenty-four courses aredivided into three zones of eight courses each, the openings in the topzone being' larger than those in the intermediate zone, and the openingsin the intermediate zone being larger than those in the bottoni zone. Innormal operation, the totaltime for hot gas to travel from the course 15to` the channel 1G is less 'han one-half a second, dividedapproxiu'iately, one-half of the time traversing the upper zone,one-third of the time traversing the intermediate Zone, and one-sixth ofthe time traversing the lower zone. ,lt inav be considered that, in thearrangement illustrated in Fig. 2, there is one direct iinpingemcnt percourse, and tivo indirect impingements per course of blocks, the directimpingements being occasioned by the direct striking of the gas on theupper surface of the block, and the indirect inipingexnents beingoccasioned by the swinging ol? the gas around the upper and lowercorners of the block. lt, therefore, follows that, in the illustrationunder consideration,

`each particle of eas is subjected to direct iinpingements in the upperzpne at the rate of at least per second, in the, interniedia'rte zone attherate of at least 48 per second, and in the lower zone at the rate ofat least 96 per secondn The indirect impingements, being twice asfrequent as the figures above given, are` in the upper Zone, at the rateof at least Gil per second, in the intermediate zone at the rate of atleast 96 per second, and in the lower zone at the rate of at least 192per second.

`While I have mentioned, in the foregoing example, one illustration ofa. construction in which certain frequencies of impingement are secured,it will be understood that said illustration is given only by way ofexample, and is not in any sense a limitation upon the meaning ordefinition of the term impingement.

I wish to emphasize vthe fact that, while l have herein-shown anddescribed a particular construction in which the features of myinvention are' shown, as used for the purpose of beati, .,9; an ovenwoll, still they may be applied with equal advantage in many instancesfor the heatingof gas or air flowing through a wall, and in thisconnection I Wish to repeat that the application of the nennen featuresof the invention to the construction shown in thedrawings is done merelybyl way of illustration and for convenience in a description andunderstanding of the invention.

l claim:

l. The method of heating a coke oven Wall or the like` which consists inleading hot in contact with the wall, and causing said gases to impingeor Contact against portions of the wall repeatedly and with in creasingviolence as the. gases travel along the u'all from the entrance towardthe exit, for the purpose of increasingly eliminating any tendency tow:rd the formation of layers of inert gas on the Wall to thereby secure auniform heatingl effect.

The method of heating a coke oven Wall or the like, which consists inpassing hot gases through the body of the Wall, and causing said gasesto contact or impinge against portions the Wall repeatedly and with anincreasing amount of violence as the gases approach the pointof exit, tothereby increasingly eliminate any tendency toward the forn'ration oflayers of inert gas on the wall, thereby giving a uniform heatingeffect.

8. The method of uniformly heating a coke oven -wall or the like, whichconsists in passing hot gases through the body of the Vall, and causingsaid gases to contact or impingeagainst portions of the Wall repeatedlyand with an increasing amount of violence as the point of exit isapproached, to thereby secure improved heattransfer between the gasesand those portions of the wall nearer to the point of exitto therebygive a substantially uniform heating effec-t with gases of decreasingtemperature.

The method of uniformly heating aV coke oven wall or the like, whichconsists in directing hot gases adjacent to the Wall, and in causingsaid gases to contact or impinge against portions of the wall repeatcdlyand withl a varying degree of violence in different portions of theWall, to thereby give a varying heat transference in dilferent portionsof the Wall, and thereby secure' a uniform temperature in the Wall,notwith-v standing the variations in temperature of the heating gases atdi'lerent points.

5, 'The method of uniformly heating a.' coke oven wall or the like,which consists in causing the gases to impinge repeatedly :and violentlyagainst portions of the wall as the gases travel from the point ofentrance toward the point of exit, the amount of impingement increasingas the point of'eNit is approached to thereby give anincreased heattransfer in those portions of the Wall nearer to the point of exit, tothereby secure `a uni-form heating effect throughout the Wall.

(l. The method of uniformly heating a colte oven wall or the like, whichconsists ile ist

to impinge against portions of the wall, the

amount of iin-pingement varying in different portions of the wall tothereby give an improved heat transference in those portions of the wallwhere the temperature of the gases is reduced and thus secure a uniformheating effect, notwithstanding the Variation in gas temperature.

8.l The art of transferring heat between a coke oven wall and a gas,which consists in leading the gas into contact with the wall andsubjecting said gas while in contact with the wall to repeated andviolent impingement with portions of the wall, the amount vofimpingement against different portions of the wall varying, to therebysecure a desired heating effect at different points during the travel ofthe gas with respect to the wall.

9. The art of transferring heat between a.

coke oven wall and a gas, which consists in subjecting said gas while incontact with the wall to repeated violent impingement with portionsofthe wall to thereby improve the transfer of heat between the gas andthe wall, the amount of impingement varying at different portions ofthewall according to Athe requirements.

l0. The art of transferring heat between a coke oven wall and a gas,which consists in causing the gas to impinge with Violence againstdifferent portions of the wall to thereby insure a maximum'heattransference between the gas and the wall, the amount of impingementvarying at different portions ofthe wall according to requirements.

11. The art of transferring heat between a coke oven wall and a gas,which consists in` causing the gas to travel in contact with the wall,and in successively increasingly elimin ating the tendency toward theformation of a layer of inert gas on the wall.

12. The art of transferring heat between a coke oven wall and a gas,which consists in causing the gas -to travel in Contact with the wall,and in eliminating in successively increasing degree in differentportions of the wall, the tendency ltoward the formation of a layer ofinert gas on the wall.

l ARTHUR ROBERTS. Witnesses:

THOMAS A. larnarrro, Jr., EPHRAIM BANNING.

